(EN) It is intended to provide a method of modifying the isoelectric point of an antibody while sustaining the antigen binding activity thereof which comprises modifying the charge of at least one amino acid residue which can be exposed on the surface of the complementarity determining region (CDR). Further, it is intended to provide a method of purifying a multispecific antibody by modifying the isoelectric point thereof and a method of improving the drug kinetics in plasma of an antibody having a modified isoelectric point. Furthermore, it is intended to provide an antibody having a modified isoelectric point, a medicinal composition comprising the antibody as the active ingredient and a method of producing the same.
(ZH) 本发明人等提供：通过改变能够暴露于互补性决定区(CDR)表面的至少1个氨基酸残基的电荷，在保持抗体的抗原结合活性的同时改变抗体的等电点的方法。本发明还提供通过改变等电点来纯化多特异性抗体的方法和通过改变等电点来改善抗体的血浆中药物动力学的方法。并且，本发明提供等电点被改变的抗体、含有该抗体作为有效成分的医药组合物及其制造方法。